Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The 'READ-ONLY' prefix and the safety profile are already covered by readOnlyHint/destructiveHint annotations, but the description adds real value: it discloses that legacy get_inbound_shipments returns nothing for plans created in the current workflow, and it enumerates what the response contains. No auth, rate-limit, or pagination behavior is described.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loads the READ-ONLY constraint and the core action, then adds the differentiator. It is reasonably dense, though the parenthetical API/version detail and the duplicated status list make it slightly heavier than necessary.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully names the returned fields (id, name, status, marketplaces, timestamps), which compensates well. It leaves pagination behavior and the meaning of the account_id outpost concept (documented in Italian in the schema) unaddressed, but is otherwise sufficient for a simple read-only list tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so all three parameters (status, page_size, account_id) are already documented in the schema, including the status enum values which the description merely echoes. The description adds no syntax, default, or interpretation detail beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource (list FBA inbound plans), names the exact API version/workflow (Fulfillment Inbound v2024-03-20, 'Send to Amazon'), and enumerates the returned fields. It also explicitly distinguishes itself from the legacy get_inbound_shipments v0 endpoint, which is the key look-alike.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear positive usage guidance ('Use to list the seller's actual inbound plans/shipments and their status') and rules out the legacy endpoint for current-flow shipments. It does not, however, differentiate itself from the singular sibling get_inbound_plan or cancel_inbound_plan, so the routing guidance is strong but incomplete.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.